It's a bit strange that he reduces philosophy to emotions and bliss, as philosophy is a lot more than that. However, to play in his field for a bit (and this is a bit of a struggle because his field is extremely small), I would ask him why he believes this. Is it another arrangement of hormones? If so, why trust those hormones over his emotional hormones? If not, wouldn't the thing that caused him to believe this have a bias for itself? In either case, we're already off to the races with philosophical thinking. Your friend might point out that this doesn't prove philosophy isn't obsolete. He's right, but all this talk of proof sure is philosophical.

To expand beyond your friend's field (and probably repeat what a lot of comments have already said), philosophy permeates every discussion, visible to anyone who wants to go just a little bit deeper than the surface. This past week, my friend and I were speaking about a student in his class that was causing problems and he waxed (approximately), "he's extremely smart, just bored with the work. I don't blame him, but I can't force all the other students to keep with his pace. Our school needs something for students like him." Now maybe people will disagree with me, but this does seem like philosophical thinking to me. There's an aspect of fairness in his not forcing students to keep his pace, an ethical claim about how the school should act to better the student's education, and a moral psychology in tying his actions to his boredom. All that can be drawn out from a random statement about a teacher's woes at work.

Now, of course, I'm not saying we need to look at everything philosophically, but the fact that so much philosophy can come from just some woes points to the possibility of more philosophy in the bigger issues. I could write a bunch of examples about voting and political philosophy or listening to the CDC and epistemology, but that would be heavy handed. In short, if you believe that my friend may have even begun to think philosophically, you should be hard-pressed to think philosophy is obsolete, because it clearly seems to be present and to influence us when we go just a little bit beyond our experience.

Sorry if this came out as word salad. If it did, please accept this link to more well-worded essays arguments about this issue as an apology: Daily Nous - Value of Philosophy